Mixer



E. A. REIFFEN June 26, 1962 MIXER 2 Sheets-Sheet 1 Filed July 28, 1960 Jnvenzor: Ens-rt AlFnrJ RM'FFIM ABtaRNE'YS June 26, 1962 E. A. REIFFEN 3,041,051

MIXER Filed July 28, 1960 2 Sheets-Sheet 2 Fig. 5

Jn van for:

5 JWHM A ti: nnvsys' United States Patent MIXE This invention relates to a mixer. In particular, the invention is directed to a continuously operating apparatus for dispersing, homogenizing and emulsifying materials and in which a horizontally positioned mixing vessel or housing contains a plurality of spaced stator plates through which are openings extending parallel to the longitudinal axis of the vessel and a plurality of rotor plates mounted on an axially extending shaft for rotation between the stator plates, respectively.

The object of this invention is to improve upon such an apparatus by providing areas or zones of turbulent material flow, both perpendicular to the longitudinal axis of the vessel and parallel to said axis.

In general, this and other objects of the invention are obtained by providing annular grooves concentric with the longitudinal axis of said vessel and coaxial with the rotor shaft. These grooves are in the form of annular segments separated by enlarged recesses. The rotor plates contain pins spaced around a circle, with the free ends of the pins mounted for movement in the annular grooves. During rotation of the rotor plates, the pins create zones of material turbulence in planes perpendicular to the axis of the shaft at the points where the openings through the stator plates continue into the grooves, and turbulence parallel to the axis of the rotor shaft along the pins.

Because of the simultaneous creation of the perpendicular and parallel zones of turbulence, the efficiency of the apparatus is materially increased.

The means by which the objects of the invention are obtained are described more fully with reference to the accompanying drawings, in which:

FIGURE 1 is a longitudinal cross-sectional view through the mixer;

FIGURE 2 is an enlarged detail view of a portion of FIGURE 1;

FIGURE 3 is a side view of FIGURE 2 in the direction of the arrow III;

FIGURE 4 is a side view of FIGURE 2 in the direction of the arrow IV;

FIGURE 5 is a longitudinal cross-sectional view of a modified form of mixer;

FIGURE 6 is an enlarged detail view of a portion of FIGURE 5 and FIGURE 7 is a side view of FIGURE 6 as seen from the direction of the arrow VII.

As shown in FIGURES 1 to 4, the cylindrical housing 1 has plate means composed of two stator plates 2 mounted therein and spaced by sleeves 3 which are held in position by abutting against the end covers 4. Openings or passageways 5 extend through plates 2 parallel to the longitudinal axis of the vessel 1 and are spaced around a circle.

Rotor drive shaft 6 is positioned on the longitudinal axis of vessel 1 and is journalled in the stator plates 2 and in an external hearing as shown. This shaft is driven by any suitable motor means. Mounted upon shaft 6 are three rotor plates 7 through which extend openings 8 spaced around a circle and located inwardly toward shaft 6 a distance less than that of the stator openings 5. The center rotor plate revolves between the two stator plates 2, While the two other rotor plates 7 rotate across the outer faces of each stator plate. Material to be mixed is introduced into vessel 1 therough inlet fitting 9 3,041,051 Patented June 26, 1962 and discharged from outlet fitting 10. The material thus flows through the vessel a longitudinal direction. The material flows around the outer circumference of rotor plate 7 as well as through the openings 8. Also, the material can pass only through the openings 5 in stator plates 2. These openings 5 communicate with the bottoms of annular grooves 11 concentric with shaft 6 and formed in the opposite faces of each stator plate. grooves actually are composed of enlarged recesses 12 concentric with openings 5 and separated by intervals composed of arcuate segments 13. Shearing pins 14 of circular or polygonal cross-section move between the side Walls of grooves 11. These pins are spaced around a circle and are fixed to the rotor plates 7. In the free end of each pin 14, a cupshaped recess or cavity 15 is formed. Similar cavities 16 are provided in the bottom of each arcuate segment 13 of grooves 11.

The material to be mixed enters the grooves 11 and flows only axially through stator openings 5. In order to reach stator openings 5, the material must flow along the inner and outer side walls of the annular grooves and be pushed along by pins 14. These pins push the material over openings 5, the diameters of openings 5 being slightly less than that of pin 14. By reason of such, zones or areas of turbulent material flow are created perpendicular to the longitudinal axis of vessel 1.

The concentric or parallel zones of turbulent flow are created by the rotor pins 14 and the side walls of grooves 11. At high speeds, defiective, frictional and shearing forces are created at the arcuate segments 13. In addition, the releasing of the stressing of the material within recesses 12 forms a high turbulent flow. Furthermore, at high speeds, the cavities 15 of pins 14 and the cavities 16 of grooves 11 produce cavitation efiects.

In FIGURES 5, 6 and 7, the elements corresponding to FIGURE 1 are shown with the same reference numerals. However, the stator plate means 2' are of a different form. In this modification, the stator plate is provided with groove means composed of members 17 inserted through the plate separated by open intervals and thus providing the stator openings 5 and the groove through which the rotor pins 14 move. Members 17 are spaced around a circle on each stator plate and form grooved portions 11' concentric with the axis of vessel 1. The groove portions 11 lie between side walls 17' formed on opposite sides of each member 17 As members 17 are spaced from each other, there are intervals between grooves 11 corresponding to the enlarged recesses 12 of FIGURES 1 to 4.

In the embodiment of FIGURES 5 to 7, the rotor pins 14 are also provided with cavities in their free ends, and cavities corresponding to cavities 16 of FIGURES 1 to 4 are formed in the stator plates 2 between the members 17.

Having now described the means by which the ob jects of the invention are obtained, 1 claim:

1. A mixer for continuously dispersing, homogenizing and emulsifying a material comprising a horizontal cylindrical housing, a plurality of circular spaced stator plate means mounted in said housing, a plurality of stator holes extending transversely through said stator plate means and being spaced around annular groove means formed in said stator plate means, said groove means being separated by intervals between each pair of adjacent stator holes, a drive shaft mounted on the longitudinal axis of said housing, a plurality of rotor plates secured to said shaft and extending alternately between said stator plates, rotor holes extending transversely through said rotor plates and being located radially closer to said longitudinal axis than said stator holes, a plurality of shearing'pins mounted on each rotor plate and posi- The.

tioned parallel to said axis opposite said groove means and with the free end of each pin extending into and being movable along a corresponding groove means for forming turbulent zones in the material in planes perpendicular to said axis and parallel to said axis between the walls.

of said grooves and said pins.

2. A mixer as in claim 1, said groove means comprising enlarged recesses separated by intervals composed of annular grooves of rectangular cross-section.

3. A mixer as in claim 2, each of said pins having a 10 substantially circular cross-section.

References Cited in the file of this patent UNITED STATES PATENTS 2,961,223 Dooley Nov. 22, 1960 

